Azithrimycin is effective therefore I would think that maybe something else was allowed to take root
in the Chlamydia’s place? If this isn’t the case then the
Azithromycin did not
in fact eradicate the infection and, as you suggest the doctor may want to use a different antibiotic like Doxy. I would suggest that you keep a journal, drink plenty of water, jot down these questions and others you think of and show up to your next appointment prepared to get answers.